1. Technical Field
The inventive concept relates to a nonvolatile memory device, and more particularly, to a nonvolatile memory device for preventing voltage drop of a program voltage.
2. Related Art
Flash memory devices are representative devices of nonvolatile memory devices in which data is retained when a power voltage is interrupted. In the flash memory devices, data can be electrically erased or programmed, and a refresh function for rewriting the data in a certain period is not necessary.
However, as the integration degree of the flash memory devices is increased, a voltage for programming data in a memory cell region is gradually dropped. The voltage drop of the program voltage may be caused by parasitic capacitance generated in the nonvolatile memory devices. Even when the program voltage of a high level is applied, the program voltage which substantially reaches a memory cell is lower than or equal to the preset program voltage of a high level. Therefore, the resistance distribution of a nonvolatile memory cell is dispersed according to the application of the program voltage lower than equal to the preset high voltage.